Monitor Arm

The present invention relates to an apparatus, commonly called a monitor arm, that designed to support one or more electric displays. More particularly, the present invention relates to a device for limiting the rotation of a monitor arm arranged for engaging a user device such as a computer monitor, the monitor arm including a base portion and a rotatable arm portion or a monitor pole.

Frequently, a user device, such as a computer monitor or flat panel display is secured to a support surface, such as a desk or wall, via a monitor arm. The monitor arm may include a base portion mounted to a support surface such as a desk or wall, and a swiveling extension arm that connects the base portion to the user device so that the user device is movable with respect to the support surface. Once the user device is attached to the mounting apparatus, the user may be permitted to rotate the user device about an axis of rotation of the base. In such mounting apparatuses, however, there may be a need to limit the degree to which the user device is permitted to rotate, or there may be a need to prevent rotation entirely. In one example, it may be beneficial to limit rotation of the user device to prevent the user device from touching a back wall, or a left or right side wall during adjustment. Also, limiting the rotation of the user device may prevent the user device from reaching outside a service area into another service area, e.g., a service area of an adjoining desk.

The invention relates generally to a system that limits relative rotational movement of a monitor arm that may include a base portion and a rotatable arm portion connected to the base portion. The system may include a rotation limit selector that is carried on either the base portion or the rotatable arm portion of the monitor arm and includes a limit projection that extends parallel to an axis of rotation. A rotation limit bushing is carried on the other of the base portion or rotatable arm portion of the monitor arm and includes a shoulder having a slot extending in a circular arc about the axis of rotation. The limit projection is slidably inserted into the slot to limit the extent of rotation of the rotatable arm portion with respect to the base portion.

The ensuing detailed description provides preferred exemplary embodiments only, and is not intended to limit the scope, applicability, or configuration of the invention. Rather, the ensuing detailed description of the preferred exemplary embodiments will provide those skilled in the art with an enabling description for implementing the preferred exemplary embodiments of the invention. It being understood that various changes may be made in the function and arrangement of elements without departing from the spirit and scope of the invention, as set forth in the appended claims.

To aid in describing the invention, directional terms are used in the specification and claims to describe portions of the present invention (e.g., upper, lower, left, right, etc.). These directional definitions are merely intended to assist in describing and claiming the invention and are not intended to limit the invention in any way. In addition, reference numerals that are introduced in the specification in association with a drawing figure may be repeated in one or more subsequent figures without additional description in the specification in order to provide context for other features.

illustrates an overall view of one possible configuration of a monitor arm assemblyon which the rotation limit system of the present invention could be utilized. The specific configuration of the monitor arm assemblymay be selected depending upon the particular type of workspace object it will connect to. For example, the monitor arm assemblymay include a base assemblythat is formed of a base castingthat is mounted to a base pad. The base padmay include a cover. As best shown in, the monitor arm assemblymay include a clampprovided as part of the base assemblyfor clamping the monitor arm assemblyto the top of a desk or other horizontal surface. Alternatively, the clampcan be employed to connect the monitor arm assemblyto a slat wall or other vertical surfaces.

A user device (not shown) may be secured to the monitor arm assemblyby securement to a plate assembly. The user device could be a conventional display screen such as a computer monitor. The plate assemblymay be secured to a tilt assemblythat is pivotable along a horizontal axis to enable a user to adjust a tilt angle of the user device once mounted to the plate assembly. The tilt assemblymay be mounted to the first endof a dynamic arm assembly. The dynamic arm assemblymay include a castingand a cable coverfor protecting cables. At its second end, the dynamic arm assemblyis pivotably mounted to the first endof an angled arm assemblyto form an upper joint. The angled arm assemblymay include a castingand a cable cover. At its second end, the angled arm assemblyis pivotably mounted to the base assemblyto form a lower joint.

illustrate the details of the rotation limit system of the present invention installed at the lower joint. In particular, the rotation limit system is comprised of four main components: a mount post, a rotation limit bushing, a locking bushing, and a rotation limit selector. As described in detail below, when the locking bushingand rotation limit selectorare assembled to the second endof the angled arm assembly, and the mount postand rotation limit bushingare assembled to the base assembly, these components interoperate to limit the degree of rotation of the angled arm assemblywith respect to the base assemblyto a greater or lesser extent based on user preference. Similarly,illustrates the details of the rotation limit system of the present invention shown installed at the upper joint, which utilizes the same components as described above. When the locking bushingand rotation limit selectorare assembled to the second endof the dynamic arm assemblyand the mount postand rotation limit bushingare assembled to the first endof the angle arm assembly, these components interoperate to limit the degree of rotation of the dynamic arm assemblywith respect to the angled arm assemblyto a greater or lesser extent based on user preference.

As best shown in, at the lower joint, the mount postincludes one or more alignment featuresto ensure that the mount postis inserted in a particular rotational position within the central opening of the base castingwith the threaded holefacing forward. The threaded holemay be utilized to receive a set screw therethrough to secure the mount postwithin the base casting. The mount post is secured within the central opening of the base castingutilizing a plurality of mounting screwswhich extend upwardly from the bottom of the base casting. Optionally, a plurality of upwardly facing protrusions (not shown) may be positioned at the bottom of the castingto ensure that the mount postwill fully seat within the base castingat only one rotational position. For example, four protrusions may be positioned equidistantly about the interior circumference of the base castingand may include a pair of wider protrusions positioned adjacent a pair of narrower protrusions to ensure proper rotational positioning of the mount post.

Referring again to, the rotation limit bushingis provided with a shoulder portion surrounding a tube portion having a central openingto enable seating within a central opening of the mounting post. As best shown in, the shoulder portion of the rotation limit bushingincludes a plurality of curved slots,that extend about the central opening. For example, a first curved slotmay extend along a circular arc of approximately 180 degrees from a left stop located at one end of the arc to a right stop located at the opposite end of the arc. Similarly, a second curved slotmay extend along a circular arc of approximately 90 degrees between a left stop and a right stop. The length and number of the curved slots shown is merely exemplary and a greater or fewer number of curved slots having the same or different arc lengths could be used. As discussed in detail below, when selected, the first curved slotprovides a greater extent of rotation of the angled arm assemblywith respect to the base assembly, e.g., 180 degrees, and the second curved slota lesser extent of rotation, e.g., 90 degrees.

A threaded center boltis arranged to extend through the central openingof the rotation limit bushingand the central opening of the mount postand secure to a threaded hole of the clampto retain the rotation limit bushingand the mount posttightly against the base casting. As illustrated in, an adjustment tool, e.g., a hex wrench, may be used for tightening these components. Together, the central openings of the mount postand the rotation limit bushingdefine an axis about which the angled arm assembly rotates with respect to the base assembly.

As best shown in, at the second endof the angled arm assembly, the castingis provided with an internal recess sized and shaped to house the locking bushingand rotation limit selector.shows that the locking bushingis provided with a centrally located slotand may be affixed within the castingutilizing any suitable hardware, e.g., screws.shows that the rotation limit selectorincludes a cylindrical main bodyhaving a hex fittingat each end, and a cylindrical actuation elementthat extends downwardly from the main body. When positioned within the casting, the main bodyof the rotation limit selectoris captive within the through openingon the castingexposing the hex fittingsat each end, and the actuation elementextends through the slotof the locking bushingand into the shoulder portion of the rotation limit bushingwhere the central openingand curved slots,are located.

Referring now to, an adjustment toolis provided. The adjustment toolincludes a handlehaving a short hex armextending in one direction and a long hex armextending in another direction from the handle. As shown in, the base assemblyincludes an area for storage of the adjustment tool. Utilizing the adjustment tool, a user can slide the rotation limit selectorwithin the castinginto any one of three different positions, i.e., a central position, a left position, and a right position. Thus, the adjustment toolcan be used to perform nearly every adjustment function for the monitor arm assembly.

As shown in, insertion of the short hex arminto the through openingof the castingin the direction of arrowcauses the rotation limit selectorto slide into the central position and causes the actuation elementto insert into the central openingof the rotation limit bushing. (Insertion of the short hex armfrom the opposite side also causes the rotation limit selectorto slide to the central position.) With the actuation elementinserted into the central opening, the angled arm assemblyis free to rotate a full 360 degrees with respect to the base assembly.

Referring now to, insertion of the long hex arminto the through openingin the direction of arrowcauses the rotation limit selectorto slide to the left position and causes the actuation elementto insert into the curved slot() of the rotation limit bushing. With the actuation elementinserted in the curved slot, the angled arm assemblyis limited to rotate 180 degrees with respect to the base assembly.illustrates this range of rotation at arrow.

Insertion of the long hex arminto the through openingfrom the opposite side of the castingin a direction opposite to arrowcauses the rotation limit selectorto slide to the right position and causes the actuation elementto insert into the curved slot() of the rotation limit bushing. With the actuation elementinserted in the curved slot, the angled arm assemblyis limited to rotate 90 degrees with respect to the base assembly.illustrates this range of motion at arrow. The rotation limit selectoris provided with ball nose plungersthat apply a downward force on the actuation element as it moves across ramps and detents located on the shoulder of the rotation limit bushing.

As best seen in, the mounting postis provided with a plurality of semicircular notches spaced equidistantly about its top edge. For example, as best shown in, eight notches are provided at 45-degree spaced intervals about the top edge of the mounting post. In this manner, the rotation limit bushingmay be oriented on the mounting postto adjust the positions of the left and right stops of the curved slotsandthus shifting the arc through which the angled arm assemblyrotates with respect to the base assembly.

As best seen in, the locking bushingis provided with a quick-release mechanismincluding a push-button actuatorand a pivotable lever armhaving a catchat a distal end. The mount post, over which the locking bushingis assembled, is provided with an upper recessto receive the catch, and a lower recessto provide clearance when the push-button actuatoris depressed by the user. Once depressed, the catchreleases from the upper recessenabling easy removal of the angled arm assemblyfrom the base assembly. Thus, the actuator, which enables disassembly of the joint is an integrally-formed part of the locking bushing. Utilizing the adjustment tool, the center boltmay be loosened enabling adjustment of the orientation of the rotation limit bushingon the mounting postas discussed above. Once adjusted, center boltmay be re-tightened and the angled arm assemblyreattached to the base assembly.

illustrate the details of the rotation limit system shown installed at the upper joint. In this embodiment, elements shared with the rotation limit system installed at the lower jointare represented by reference numerals increased by factors of 100. For example, the rotation stop bushingincorresponds to the rotation stop bushingin. In the interest of clarity, some features of this embodiment that are shared with the first embodiment are numbered inbut are not repeated in the specification.

Similar to the rotation limit system shown installed at the lower joint, the rotation limit system of the upper jointis comprised of a mount post, a rotation limit bushing, a locking bushing, and a rotation limit selector. As best shown in, the mount postis received within a recess of the castingat the first endof the angled arm assembly. The rotation limit bushingis seated within the mount post. As best shown in, a threaded center boltextends through these components and into a threaded hole in the castingto retain these components tightly against the casting. Thus, mount postand the rotation stop bushingare retained in the lower portion of the joint by the bolt, and the locking bushingand the rotation limit selectorare retained in the upper portion of the joint.

As discussed above, the adjustment toolmay be used to tighten these components. At its lower end, the castingof the dynamic arm assemblyincludes an internal recess sized and shaped to house the locking bushing, which may be retained therein using any suitable hardware, e.g., screws, and the rotation limit selector. When positioned therein, the rotation limit selectoraligns with a through opening() of the dynamic arm assembly.

Utilizing the adjustment toolas described above, a user can slide the rotation limit selectorinto any one of the three different positions discussed above, i.e., a central position, a left position, and a right position, each position corresponding with a different extent of rotation of the of the dynamic arm assemblywith respect to the angled arm assembly.illustrates the 360-degree range of motion at arrowwhen the rotation limit selector is slid to the central position.

In the interest of clarity, some features of this embodiment that are shared with the first embodiment are numbered inbut are not repeated in the specification.

As demonstrated above, the rotation limit system is universal in that the same structure may be utilized in several different locations, i.e., the first joint, and the second joint. The same structure may also be utilized on other possible configurations of the monitor arm assembly. For example,illustrates an overall view of another possible configuration of a monitor arm assembly which could include a vertically oriented polemounted to a base assembly. Carried on the poleis a single yokein which the mounting post and rotation stop bushing of the rotation limit system of the present invention may be installed. The remaining components, i.e., the locking bushing and rotation limit selector, may be installed in the tilterto limit rotational movement of the tilterabout a vertical axis.

Likewise,illustrates an overall view of another possible configuration of a monitor arm assemblyon which the rotation limit system of the present invention could be utilized. The monitor arm assemblycould include a Y-adapter casingmounted to a base assembly formed of a base casting, a base pad, and a cover. At the top of each branch of the Y-adapter casing, a dynamic arm assemblyis rotatably mounted thereon. A slider track assemblyis shown mounted to each dynamic arm assembly. A user device (not shown), such as a conventional display screen or computer monitor, may be secured to a plate assemblywhich is mounted to the slider track assembly.

As best shown in, a mount postand a rotation stop bushingmay be installed at each branch of the Y-adapter casing. The remaining components of the rotation limit system (not shown), i.e., the locking bushing and rotation limit selector, may be installed within the second end of the dynamic arm assemblyto limit rotation of the dynamic arm assemblywith respect to the Y-adapter casing.

The principles of the invention have been described above in connection with preferred embodiments, it is to be clearly understood that this description is made only by way of example and not as a limitation of the scope of the invention.